It has been known for many years that the pili of pilated pathogenic organisms play an important role in the pathogenicity of these organisms. It has been shown that these pili adhere to erythrocytes and similar cells whereby the bacteria are attached thereto. The mechanism by which pili adhere to erythrocytes and the like has also been long studied. It is believed that the adhering mechanism involves a particular protein which has an affinity for a particular group or groups on the surface of mammalian cells. Heretofore, it has been believed that the adhesion is a moiety which is part of the pilus rod protein.